Cotter pin



June 2o, 1939. F, M GUY 2,162,811

COTTER PIN Filed April 16, 1938 /N VEA/Tok ATTORNEK?.v

Patented June 1939k UNITED l STATES PATENT OFFICE# CUTTER PIN Frederick M.

Guy, Detroit, Mic assigner to Guy and Murton', Incorporated, Detroit, Mich., a corporation of Michigan Application Anm 1s, 19ss,ser1a1 No. 202,416 a claims. (c1. :i5-8.5i

cipally upon friction for its operative engagement in the bolt hole and in-which' the'shape and the f size of the pin lproper determines and controls the amount of frictional engagement, thereby ensuring proper placement of the pin in the bolt hole and the operative engagement of the pin with the nut.

A sill further object of 'the invention is to provide a cotter pin which presents a double cross section of the pin stock when in an operative position to withstand the shearing effort produced by the rotation of a loosening nut.

A still further object of the invention is to provide an improved cotter pin of the resilient type which is so retained in its operative engagement in a bolt hole that vibrations and relative movements of the nut and bolt do not produce rapid repeated bending of the pin and which therefore does not fatigue the metal or cause failures thereof. vIt is an added object of the invention to provide an improved cotter pin which is very simple in construction, convenient to use and which is relatively inexpensive to manufacture.

Other objects of this invention will appear in the following description and appended claims,

reference being had tothe accompanying drawing forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

Fig. 1 is a side view partly in section of a bolt having a castellated nut and provided with a: cotter pin constructed in accordance with one embodiment of the invention, said cotter pin being shown in its operative position.

Fig. 2 is a fragmentary sectional view in the direction of the arrows, the section being taken on the line 2*--2 of Fig. 1.

Fig. 3 shows in perspective thejcotter pin of Fig. 1 removed-from the bolt.

Fig. 4 is a view similar in part to Fig. 1, the cotter pin being shown in a position just before its insertion into the bolt hole. v Fig. 5 shows the relative positions .of the parts of the pin when the same is being inserted into the bolt hole.

terminology employed herein is for the purpose -of description and not of limitation, and it is -not intended to limit the invention claimed herein Fig. 6 shows in perspective a modied form of cotter pin embodying the present invention.d

Fig. 7- is a fragmentary view partially in section showing the cotter pin of Fig. 6 in an operative position in a bolt hole. Y

Before explaining in detailthe present inven-4 tion it is to be understood that the invention is not limited in itsY application to the details of construction and' arrangement of parts illustrated in the accompanying drawing, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also it isto be understood that the phraseology or beyond the requirements of the prior art.

In the 'drawing there are shown. by way of example, three types of cotter pins embodying the present invention. In Fig. 1 there is illus- 20 trated a bolt III having a castellated Anut Il threaded thereon. The nut II-is provided with a series of diametrically, opposed recesses I2 and I3,v while the bolt I0 is provided with a transverse passage 'or bolt hole I4 formed in the threaded 25 portion of the bolt transversely thereof and adaptedto register with a pair of the opposed recesses I2 and I3 of said nut II. Inserted into `said bolt hole there is shown one form of the o cotter pin embodying the, invention. As shown 30 in Fig. 3, wherein said cotter pin is illustrated separately and in its free or uncompressed state, the cotter pin comprises a strip of resilient material, preferablya strip of spring steel of the like bent upon itself substantially at its middle 35. to provide a loop I5 and two legs I6 and I1. 'Ihe lower leg I1 is preferably formed with an upwardly inclined portion adjacent the end to facilitate ready insertion of the pin in a bolt hole. The loop I5 is substantially round and 40 its diameter is larger than that'of the hole Il, and therefore said loop forms, in fact, a head Y of the pin which cannot pass through the hole Il and therefore serves as the 'stop or the head for the pin. 45

The upper leg I6, that I s the one. which is more remote from the bolt head than the leg I1, as shown in Fig. 1 has a turned up portion or end I8 provided thereon, the bend being of substantially degrees. The size of the turned up end 60 I8 is such that when the legs 'I6 .and I'I are brought together, it can be easily passed through the bolt hole I4. As soon as the end I8 comes out from, the other side or the hole Il, opening eirort or the legs bringstlnivunper` extremity of w K the end I8 well above the hole, whereupon the removing of the pin by an application of an effort' in a direction parallel to the axis of the bolt hole I4 becomes impossible unless the legs ar'e brought together by compressing the pin.

In' the operative position of the cotter pin illustrated in Fig. 1 the upper leg I6 is in contact with the Walls of the hole Il substantially throughout 'the entire length thereof, `while the lower leg I'I contacts the hole only at the end' thereof as indicated at I9. It should be noted that since a at strip is used for making the cotter pin, only the edges thereof contact the side walls of the hole I4, and therefore in a sectional view taken substantially through the middle of -the pin the cotter pin seems not to be incontact An examination ofl with the Walls of the hole.

Fig. lv will clarify this construction.

In the modified structure shown in Figs. 6 and 7, the lower leg 20 is provided with a convex portion 20a adapted to provide additional points of contact of the pin with the walls of the -hole I4 intermediate the ends thereof. The construction here shown utilizes a hooked end portion I8.

Removal of the pin from the bolt hole can be achieved-Without the necessity of breaking the pin and the same may be used repeatedly many times. In addition, breaking oi of the ends of the pin, prevented in my cotter pin, is very undesirable, since the broken pieces may easily get between mating parts such as gears and ca use breakagethereof, or they may get in valves and cause serious, operation troubles.

- fI claim; l

y1. [A cotter pin for insertion into a bolt hole of a bolt and nut device, said pin comprising a single .flat strip of metal bent upon itself at its approxi- Y kmate middle to produce in said approximate middle4 a4 continuously curved loop substantially in Athe -form of acircle of a larger diameter than that of the bolt hole into which the pln\is intended tov be inserted, said pin having two legs adapted tocome together in relatively flatwise abutting relation when the pin is compressed and to open whenthe pin is released, one leg having a sharp hook-shaped en d upturned away from the other leg for engagement with the threaded portion of the bolt, and said other leg having its -free end extended beyond the rst leg and being curved gradually in the general direction of the vhookshaped end of said rst leg.

2r A cotter pin for insertion into a bolt hole oi a bolt and nut device, said pin comprising aY single flat strip of metal bent upon itself at itsapproximate middle to produce in said approximate middle a continuously curved loop substantially in the form of a ..circle of a larger diameter than that of the bolt hole into which the pin is intended to be inserted, said pin having two legs adapted to come together in relatively atwise abutting re-V lation when the pin is compressed and to open when the pin is released, one leg having a sharp hook-shapedend upturned away from the other leg for engagement with the nut and thethreaded portion of the bolt, and said other. leg having its A free end extended beyond the rst leg and being curved gradually in the general direction of the hookshaped end of said rst leg, said other leg engaging a wall of the bolt hole.

3. A cotter pin 'for insertion into a bolt hole o a bolt and nut device, said pin comprising a single flat strip of metal bent upon itself at its approximate middle to produce in said approximate middle a continuously curved loop substantially in the form of a circle of a larger diameter than that of the boltt hole into which the pin is intended to be inserted, said pin having two legs adapted to come together in relatively iiatwise abutting relation when the pin is compressed and to open when the-pin is released, the leg more remote from the bolt head having a sharp hook-shaped end upturned. away from the other leg for engagement with the threaded portion of the bolt, said other leg having its free end extended beyond the rst leg and having a gradual curvature in the general direction of the curvature of the hook-shaped end of said ilrst leg, and said last named leg having intermediate its ends a portion bowed out, wardly away from the rst leg for engagement with a wall ofthe bolt hole.

. y FREDERICK M. GUY. 

